The present invention relates to a die-cutting apparatus for cutting a sheet of paperboard, for example, which is being continuously fed, into a predetermined shape, and more particularly to a die-cutting apparatus which facilitates the separation of waste from a thick sheet after the thick sheet has been cut.
Generally speaking, a conventional die-cutting apparatus of the above type comprises a die cylinder which has a die secured to its outer circumference and equipped with die-cutting blades or rules arranged in a predetermined shape, and an anvil cylinder having a cover of soft material such as polyurethane plastic wound around its outer circumference. Sheets of paperboard are fed one by one from a paperboard feed table into the space between those cylinders by means of a kicker device or the like so that it can be cut into a predetermined shape by the die-cutting blades, after which it is fed out to the downstream side and stacked with the other pieces for storage. However, in such an apparatus especially when the sheet used is thick, part of the paperboard sheet being cut in the above die-cutting step is not naturally separated from the sheet, i.e., the waste frequently fails to separate from the sheet after the die-cutting step and remains thereon until it is fed out to the downstream side as it is. This makes it necessary to separate the waste from the sheet in a manual way which is a waste of human and time efficiency. As a means for eliminating such a manual operation, a method has been devised of separating the waste by a vibrator disposed in the feed path downstream of the die-cutting step for imparting vertical vibrations to the paperboard sheet. However, it is impossible to ensure the complete separation of the waste from the sheet.